Any text-based protocol would have predefined keywords with special purposes that are agreed between parties to communicate with each other. A trivial way used to reduce the size of messages is to use shorter forms to replace those long, predefined keywords. However, there may still be text patterns that are repeated or redundant in a message.
The existing technologies of text-based compression can be categorized into two different groups. One is dictionary-based and another one is to use a standard compression algorithm such as Huffman codes. Dictionary-based techniques usually use static dictionaries that are created before transmission of a message and/or dynamic dictionaries that are included in the message. Those techniques include U.S. Ser. No. 6,976,081, U.S. Ser. No. 5,999,949, U.S. Ser. No. 7,412,541, U.S. Ser. No. 6,807,173, U.S. Ser. No. 6,883,035, and U.S. Ser. No. 6,976,081. Replacing the longer words with a shorter form is a simple example of using a static dictionary at both the compressor and the decompressor. This disclosure proposes a method, Dynamic Pattern Elimination, to eliminate redundant patterns the content of which is not known a priori. The proposed method identifies the redundant patterns on the fly and does not require any dictionary.